The '''halogens''' or '''halogen elements''' () are a group (periodic table)|group
in the periodic table
consisting of five chemically related chemical element|elements
(I), and astatine
(At). The artificially created element 117 (ununseptium
) may also be a halogen. In the modern IUPAC
nomenclature, this group is known as '''group 17'''.
The name 'halogen' means 'salt-producing'. When halogens react with metals they produce a wide range of salts, including calcium fluoride
, sodium chloride
(common salt), silver bromide
and potassium iodide
The group of halogens is the only Group (periodic table)|periodic table group
that contains elements in three of the four main states of matter
at Standard conditions for temperature and pressure|standard temperature and pressure
. All of the halogens form acids when bonded to...